In the fiction of
J. R. R. Tolkien, the 'Years of the Sun' are the last of the three great time-periods of
Arda, together with the
Years of the Lamps and the
Years of the Trees. They begin with the first sunrise in conjunction with the return of the Noldor to
Middle-earth, and last until the present day. (The history of the fictional Middle-earth is to be taken fictionally as a history of the real Earth.) The Years of the Sun began towards the end of the
First Age of the Children of Ilúvatar and continued through the
Second,
Third, and part of the
Fourth in Tolkien's stories. Tolkien estimated that we are now living in the sixth or seventh age .